The present invention relates to transit concrete mixers of the type having a mixer barrel whose axis is directed forward and slantingly upward, with the barrel extension projecting over and forwardly beyond the cab. Vanes within the barrel extension are so convoluted as to deliver the concrete forward and upward through the barrel extension when the barrel is rotated in one sense, and retain and continuously agitate the concrete mix therein when the barrel is rotated in the opposite sense.
Transit mixers which discharge forwardly are not new. One type in use is shown in U.S. Pat. No. 3,334,872, dated Aug. 8, 1967; this mixer requires a special chassis with the engine in the rear. In the constructions proposed in two earlier U.S. Pat. Nos. 2,859,949 and 3,019,002, the engines are loctated immediately behind the truck cabs. All such unconventional chassis are undesirable because of high initial cost and delays and repair maintenance.